Manhole-door.



G. D. STANFORD & P. L. GRADDOGK.

' MANHOLE DOOR.

APPLICATION 111.1111 1'1111.17,19oe.

Patented 0111'. 17, 1911. H 1 ZSHBETB-SHEBT '1.

1 rnr'nrrl Q HJEDHr\dE figumgora;

G. D. STANFORD & F. L. CRADDOCK. MANHOLE DOOR. APPLIUATION FILED r1212. 1?, 190a.

1,006,413, v Patented Oct. 17,1911.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

CHARLES D. STANFORD, OIE SUMMIT, NEW JERSEY, AND FREDERICK I1. GRADDOGK, OF NEW YORK, N. Y., ASSIGNORS T0 PFAUDLER COMPANY, OF ROCHESTER, NEW YORK,

A. CORPORATION OF NEW YORK.

MANHOLE-DOOR.

Specification of Letters Patent.

Application filed February 17, 1908.

To all whom it may concern:

Be it known that we, CI-IARLEs D. STAN- FORD and FREDERIGK L. CRADDOCK, both citizens of the United States, and residents, re-

on the drawings representing like parts.

The present invention relates to a manhole door or cover and is embodied in a door or cover for a manhole in a tank or vat, the invention being especially adapted for use in connection with the glass lined tanks used by brewers for storing beer. The doors or covers for these tanks open in wardly, and it is desirable, therefore, that they should be supported, instead of being bodily removed, when opened by an external support, for the reason that an internal support is impracticable in a tank or vat of this kind. Furthermore, it is desirable that the support should be of such a nature that the manhole cover, when the manhole is open, should be prevented from coming in contact with and damaging the glass lined interior of the tank.

In accordance with the invention, the manhole cover which, when closed, is clamped against the inner wall of the vat by means of a bolt and a bridge which engages the outside of the tank at the margin of the hole, is provided with a supporting member or carrier which is connected with the cover and movably supported upon the outside of the tank, so that it can be moved in opening the hole, at the same time affording a support for the cover in any position thereof. This carrier is herein shown as a slide arm connected with the cover near one end thereof and bent so as to extend beyond the cover and form a bow or loop which admits of the cover being moved entirely beyond the opening when it is opened to afford access to the interior of the tank. The carrier is held in a guideway outside of the tank, the said guideway being so arranged that the carrier can be moved longitudinally therein to open the manhole, the guide at the same time affording a firm support for the cover.

Figure 1 is a front elevation of a portion of a vertical tank having a manhole cover embodying the invention applied thereto; Fig. 2 is a horizontal section through the manhole; Fig. 3 is a detail showing the manhole cover alone; Fig. 4 is a side elevation showing a modification of the guide member adapted for use with a horizontal tank; Fig. 5 is an end elevation of a horizontal tank also showing this modification.

The cover a, which is usually oval in shape, may be of any suitable or usual construction, being large enough to overlie the inner wall of the tank around the manhole so as to close the said manhole tight when clamped in position. In the construction shown, the cover a is provided with a gasket a fitting the inner wall of the tank, and, when the manhole is closed, the said cover is clamped against said inner wall by means of a bolt Z2 and nut b which cooperate with the .bridge member 0 provided with end supports 0 to bear against the outer surface of the tank at opposite sides of the opening. When the manhole is opened, it is desirable to carry the cover clear of the opening without attempting to remove it from the interior of the tank, and at the same time to keep it supported so that it can be easily moved back into position to close the opening. It is further desirable to keep the cover clear of the inner wall of the tank in order to prevent damage, this being especially important in the case of tanks having a glass lining or interior surface finish liable to injury. In accordance with the invention, therefore, the cover a is provided with a supporting member or carrier a which is capable of movement in a guide member 0?, the said carrier and the guide member being so related to each other that, with exception of the movement desired, the connection between the two is firm enough to afford an adequate support for the cover in anyposition. In the construction shown, the carrier a is in the form of a slide, while the guide d is in the form of a yoke, it being obvious that the carrier a can be moved longitudinally in said guide with perfect freedom, although the said guide, in connection with the carrier of, constitutes a firm support to prevent dropping or sagging of the cover a when freed from the clamping bolt 6.

In Fig. 2, the cover is shown in dotted line position as moved from the opening,

the member a being curved or bowed, as indicated at a*, so as to project slightly beyond the edge of the cover a, thus making .it practicable to move the cover entirely beyond the opening and expose the whole area thereof.

The carrier at is capable of yielding transversely in the direction outward from the tank to admit of the cover being drawn outward by the bolt 6, so as to be seated tightly, and it preferably is tempered to constitute a spring, the tendency of which is to spread slightly at the bent or bowed portion a so that when the clamping bolt 6 is loosened, the cover will spring inward and free itself from the opening.

It is necessary, in order to open the manhole, that the clamping bolt 12 and bridge piece a should be removed, and in the construction shown, the bolt 6 is provided with an oblong head 6 adapted to pass through a slot a in the cover a into an undercut recess 0; indicated by dotted lines, Fig. 3, after which a half turn of the bolt will lock the same to the cover. The carrier a is also provided with a slot a through which the bolt 1) may be freely passed.

The guide member cl in a vertical tank may consist of a strip of metal bent, as indicated, to afford the guide socket for the member a being provided with flanges d at opposite ends which can be bolted to the flanges of the tank sections. It is desirable, in any event, to secure the guide to the tank externally, so that the walls thereof need not be perforated, and, as shown, the flanges of the tank sections may conveniently be utilized for the purpose. In a horizontal tank where the manhole is in the end, as shown in Figs. 4 and 5, the guide d may be secured at one end only, as shown at (Z the said guide being bent to conform closely to the contour of the tank end and having a projecting portion (Z which engages the surface of the tank, whereby the metal is slightly sprung by tightening the bolt or clamp which holds the part 03 By this construction, the cover support ing carrier and its guide are entirely external, and are properly secured to the tank without any perforation of the shell, which is a great advantage in tanks of this character, as there is liable to be leakage and damage to the lining when bolts or other fastenings are used that pass through the shell to the inside of the tank.

Claims:

1. The combination with the tank or vat; of a manhole door located within said tank or vat, and adapted to be clamped against the inner wall thereof; and an external supporting carrier for the door and an external guide member for said carrier secured to the exterior of the tank in which guide member said carrier is movable to move the door into and out of register with the opening.

2. A manhole door located inside of a vat or tank and provided with a bow-shaped external supporting carrier connected with the outside of the door and extending along the outer surface of the tank beyond the opening; and a retaining guide member in which said carrier is longitudinally movable, substantially as and for the purpose described.

8. A manhole door located within a tank or vat; a bowed yielding support connected with said door and held in position against the outer wall of the tank; a bridge piece for clamping said door against the inner wall of the tank; and a bolt having an elongated head to cooperate with an undercut recess in the cover, said bolt co-acting with said bridge to clamp the cover in place.

4. A manhole door located inside of a tank or vat; means for clamping said door against the inner surface of the tank to close the manhole; a sliding carrier for said door located outside of the tank; and a guide for said carrier secured to the outer surface of the tank.

In testimony whereof, we have signed our names to this specification in the presence of two subscribing witnesses.

CHARLES D. STANFORD. FREDERICK L. CRADDOCK. Witnesses:

THOS. P. MULRY, JOHN W. SANGER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

' Washington, D. 0. 

